1. Field of the Invention
The present invention relates to an ink jet printer, and more particularly to an ink jet printer head capable of reducing a number of pads which are increased in accordance with the increment of nozzles, by using a device having a single input and multiple outputs.
2. Description of the Background Art
Generally, an ink jet printer head includes a plurality of actuators, nozzles corresponding to the respective actuators, and actuator finding circuits for selecting the nozzle and for ejecting ink through the selected nozzle. Generally also, a plurality of nozzles are divided into a plurality of groups, while the actuator finding circuits are divided into a direct drive method and a drive method of matrix structure (hereinafter referred to as xe2x80x9cmatrix drive methodxe2x80x9d), respectively.
As for the matrix drive method, since the nozzles are arranged in rows and columns, the lines are not increased in proportion to the number of nozzles when the nozzles are increased. However, the problem still arises in that the number of pads is increased in proportion to the increased rows and columns.
As for the inkjet printer, since the increase of the number of heads employed to enhance both printing quality and speed results in the increase of the number of pads which connect the signal lines of the heads, the manufacturing cost of the printer heads is increased, while the yield of the printer heads is decreased.
An exemplar of the art, U.S. Pat. No. 5,028,812 for Multiplexer Circuit issued to Bartky discloses a multiplexer circuit used in an inkjet printer. U.S. Pat. No. 4,714,935 for Ink-jet Head Driving Circuit issued to Yamamoto et al., U.S. Pat. No. 5,936,644 for Head Driving Device of Ink-jet Printer issued to Ono et al., U.S. Pat. No. 5,541,630 for Injet Print Head and Inkjet Printer issued to Ema et al., U.S. Pat. No. 4,409,596 for Method and Apparatus for Driving an Ink Jet Printer Head issued to Ishii, U.S. Pat. No. 4,471,363 for Method and Apparatus for Driving an Ink Jet Printer Head issued to Hanaoka, U.S. Pat. No. 6,053,596 for Ink-jet Printing Device and Driving Circuit Used in the Ink-jet Printing Device issued to Nakano et al., and U.S. Pat. No. 5,821,953 for Ink-jet Head Driving System issued to Nakano et al. disclose ink jet printer heads and techniques for driving an ink jet printer head.
The present invention has been made to overcome the above-described problems of the prior art, and accordingly, it is an object of the present invention to provide an ink jet print head capable of reducing the number of pads which are increased due to the increased nozzles, by using a device having a single input and multiple outputs.
It is another object to have an ink jet printer head driver circuit that can be contained in a single semiconductor microchip.
It is yet another object to have an inkjet printer head that reduces the number of lines feeding the nozzles.
It is another object to reduce the cost of manufacture of the ink jet printer by reducing the complexity of the driving circuit for the ink jet printer head.
The above objects are accomplished by an ink jet printer head including a first unit having a first input terminal and a plurality of output terminals, an externally applied first signal transmitting into the first input terminal, the first unit outputting a second signal from the applied first signal, the second signal being outputted through a first one of the plurality of output terminals sequentially by order of the first signal inputted through the first input terminal, a first signal line conducting the second signal from the first output terminal of the first unit, a second input terminal having an externally applied third signal, a second signal line conducting the third signal from the second input terminal, an electronic switch accepting the second signal from the first unit through the first signal line and the third signal from the second input terminal through the second signal line, an actuator electrically controlled by the electronic switch, and a nozzle ejecting ink through a control of the actuator, the nozzle ejecting ink when the third signal and the second signal is received by the electronic switch.
The first signal is generated in accordance with a conveyance direction and position of the head, while the second signal is generated in accordance with image data. The first unit includes a multiplexer, while the ink jet printer head is made of a semiconductor chip.
By the above-described structure, even when the number of nozzles in the ink jet printer heads is increased, since the number of inputting lines for the multiplexer still remains one, the number of pads does not increase as much.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by the practice of the invention.